1. Field of the Invention
The present invention relates to an image display apparatus and an image photographing apparatus, and in particular, to an image display apparatus which displays an image represented by image information on a display device, and an image photographing apparatus which includes the image display apparatus.
2. Description of the Related Art
In general, an image photographing apparatus such as a digital still camera, a digital video camera, or the like is provided with a display device which is formed by an LCD or the like in order to enable confirmation of a photographed image or a played-back image at a time of photographing or playing back an image. Among various image photographing apparatuses, some apparatuses have a function in which the photographed image or the played-back image which is displayed on the display device can be displayed in an enlarged manner in accordance with a designation from a user. This function is effective, for example, in a case of confirming the focus or exposure at the time the image was photographed.
Japanese Patent Application Laid-Open (JP-A) No. 6-153071 discloses, in relation to the above-described art, an image signal processing mechanism in which image processing such as enlargement/reduction, rotation, or the like of an image can be easily carried out when the stored image data is played back.
Here, in the image photographing apparatus, the resolution of the photographed image (the number of pixels of the image data obtained by photographing) is an important factor which relates to the image quality of the photographed image, and technology is advancing at a pace such that resolution becomes higher year by year. Accordingly, there arises a problem that when the photographed image or the played-back image which is displayed on the display device is displayed in an enlarged manner, it is difficult to know which portion of the original image is being displayed in an enlarged manner. Especially, when the original image is an image obtained by photographing a scene in which the same type of objects are aligned in succession, or the like, it is difficult to determine which portion of the original image is being displayed in an enlarged manner.
The above-described problem is not limited to image photographing apparatuses. In an apparatus which has functions of displaying an image on a display device and of displaying the displayed image in an enlarged manner (e.g., an apparatus which has a function of simply playing back an image), for example, when the surface area of a display surface of the display device is small and a display range when an image is displayed in an enlarged manner is limited, it is difficult to judge which portion of the image is being displayed in an enlarged manner.